Lance Armstrong was in Mooresville April 17 to do some testing at A2 Wind Tunnel off Mazeppa Road.
Before he arrived, the world's most famous cyclist let nearly 2.5million people know. But what he did here was strictly private.
"Heading to Charlotte and a visit to the A2 wind tunnel," Armstrong tweeted to his followers on Twitter.com at 10:15 a.m. April 10. "Testing a few things."
Top-secret things, as it turns out.
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"I cannot comment about what they were testing, but he was here on Saturday doing some aerodynamic testing for the 2010 season," A2 general manager David Salazar said.
Wind tunnels are long chambers more commonly associated with car testing. Gary Eaker, former aerodynamics chief at Hendrick Motorsports, opened A2 several years ago beside his larger AeroDYN Wind Tunnel.
A2's wind tunnel rises to about 30 feet at one end. Its fans sound like a jet engine throttling up. A computer system analyzes whether riders gained or lost time based on such factors as how they place themselves on a bike and even which helmet they wear.
Other professional bicyclists from across the country also test at A2 Wind Tunnel in efforts to get an edge on the competition.
A2 gained more fame when the U.S. men's bobsled team won Olympic gold at the Vancouver Winter Games this year. U.S. men's and women's bobsledders tested at A2 months before the games to hone their competitive edges.
Gigantic electric fans at A2 pull air at up to 85 mph to simulate racing speeds and study how changes in the way competitors position themselves can improve performance.
"It's like NASCAR," champion men's bobsledder Steve Holcomb told the Observer at A2 months before his team brought home the gold for the first time in 62 years. "You're always looking for a little edge. Shave a little here, shave a little there. Every little thousandth of a second counts."
The same holds true with top cyclists such as Armstrong, who by 8 that night was already tweeting that he was back home in Austin, Texas.